---
id: "CVE-2026-85101"
page: "https://infrastack.ai/live/CVE-2026-85101"
kind: "vulnerability"
aliases: ["CVE-2026-85101"]
title: "Synology DiskStation: rsync auth bypass lets remote attackers read and write files"
severity: "high"
cvss: 8.6
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["dsm", "infrastructure", "nas", "rsync", "self-hosted", "synology"]
not_affected_if: ["patched-dsm", "rsync-disabled"]
published_at: "2026-11-12T04:17:21+00:00"
first_seen_at: "2026-11-12T04:47:10+00:00"
updated_at: "2026-11-12T04:47:39+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-85101", "first_seen_at": "2026-11-12T04:47:10+00:00"}]
exploit_sources: []
---

# Synology DiskStation: rsync auth bypass lets remote attackers read and write files

Link for people: https://infrastack.ai/live/CVE-2026-85101 (this .md is for agents)

The rsync service in Synology DiskStation Manager has an authentication bypass through an alternate path or channel. A remote attacker can read specific files, write arbitrary files, and cause limited denial of service.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed DSM version in Control Panel > Info Center; compare it with the fixed versions below.
- Check whether the rsync service is enabled in Control Panel > File Services > rsync.

## Fix

- Upgrade DSM to `7.2.1-69057-13` or later on the 7.2.1 branch
- Upgrade DSM to `7.2.2-72806-10` or later on the 7.2.2 branch
- Upgrade DSM to `7.3.2-86009-5` or later on the 7.3.2 branch
- Upgrade DSM to `7.4.1-90080-1` or later on the 7.4.1 branch

## Timeline

- 2026-11-12T04:47:10+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-85101

## From the sources

An authentication bypass using an alternate path or channel vulnerability in the rsync in Synology DiskStation Manager (DSM) before 7.2.1-69057-13, 7.2.2-72806-10, 7.3.2-86009-5, and 7.4.1-90080-1 allows remote attackers to read specific files, write arbitrary files, and conduct limited denial-of-service attacks.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_